In mobile communications networks, a home location register is a database that stores permanent subscriber information. The HLR is an integral component of CDMA, TDMA, and GSM networks. The HLR is maintained by the subscriber's home carrier and stores pertinent user information, including address, account status, location, and preferences. The HLR interacts with a mobile switching center (MSC), which is a switch used to setup and tear down calls to and from mobile subscribers.
HLRs store the above-described information for each subscriber in a particular carrier's network. In other words, an HLR database may include an individual database record for each subscriber. Since many mobile carriers or service providers have millions of subscribers, HLR databases have become large. When an HLR database is located on a single computer in a particular carrier's network, signaling traffic to and from the HLR and processing load on the HLR becomes a bottleneck.
One conventional method for reducing the signaling traffic and processing load on HLRs is to distribute HLR databases among multiple physical HLR nodes. In such a distributed database environment, each of a carrier's HLRs may include a predetermined subset of the subscriber records of a particular mobile carrier. If the subscriber records are distributed equally among the multiple HLRs, the processing load on the HLRs can be reduced by a factor of n, where n is the number of HLRs. However, in order to distribute subscriber records among multiple HLRs, signaling message routing intelligence must be built into the network so that other network nodes will be able to locate a particular subscriber record. In particular, mobile subscriber identification information must be derived from a signaling message and translated into an HLR address. In GSM networks, mobile subscriber ISDN (MSISDN) and international mobile subscriber identity (IMSI) numbers can be used to identify mobile subscribers. In IS-41 networks, mobile directory numbers and mobile identification numbers can be used to identify mobile subscribers. These numbers can be translated into the point code in SS7 networks or IP address in IP networks of the HLR that contains a particular subscriber's information.
In conventional mobile communications networks, the HLR address translations were performed by mobile switching centers. Each mobile switching center included a database that assigned a range of subscriber numbers to a particular HLR. One problem with this conventional range-based routing is that it limited mobile service providers' flexibility in assigning subscriber numbers to HLRs. The mobile service provider was required to assign a range of subscriber numbers to each HLR. Requiring each HLR to be assigned a range of subscriber numbers limited the service providers' ability to efficiently load share between multiple HLRs. In addition, the subscriber was prevented from porting numbers into an HLR when the numbers were not within the particular range of numbers assigned to that HLR. Similarly, when a subscriber number is ported out of an HLR, messages for the particular subscriber would continue to be routed to that HLR even though the subscriber's record was no longer there.
In order to avoid these difficulties associated with conventional range-based HLR routing, flexible numbering systems have been developed. One such flexible numbering product is G-FLEX, available from Tekelec of Calabasas, Calif. According to the G-FLEX product, tables in a signal transfer point are used to map individual subscriber IMSI and MSISDN numbers to HLR addresses. Another product, referred to as application location register or ALR available from Alcatel includes two databases in a signal transfer point that map subscriber numbers to HLR addresses. Yet another product that includes a database that allows service providers to flexibly assign subscriber numbers to HLRs is the virtual home location register or the flexible numbering register available from Ericsson.
The subscriber-number-to-HLR address translation databases can become large due to the number of subscribers in a particular service provider's network. In some instances, these databases can include millions of records. Due to the large size of these databases, provisioning the translation in the databases can be both time and labor intensive. Conventionally, these translation databases have been provisioned manually. That is, a technician or other individual is required to manually enter the translation data for each translation into the database. This manual provisioning process is time and labor intensive and increases the likelihood of erroneous translation data being entered.
One automatic provisioning solution has been proposed in which a signal transfer point learns mobile subscriber ISDN (MSISDN) numbers based on received signaling messages. However, not all mobile signaling messages routed to HLRs include MSISDN numbers. Moreover, this conventional method assumes that IMSI-to-HLR address translations have been provisioned manually. This reliance on manual provisioning of IMSI numbers includes the same problems of increased time, labor, and likelihood of error. Moreover, if the IMSI-to-HLR address translations are not provisioned in advance, this conventional solution does not work. For example, this conventional solution discusses leaning MSISDN-to-HLR mappings using InsertSubscriberData MSISDN parameters and CgPA E.164 addresses for messages received on HLR links. InsertSubscriberData messages are sent from an HLR to a VLR in response to location updating by the VLR. In order for the VLR to perform a location updating transaction, the VLR must be able to send an UpdateLocation message to the correct HLR. Since UpdateLocation messages have IMSIs and not MSISDN parameters, one conventional method for sending the UpdateLocation message to the correct HLR is for the VLR to place the mobile subscriber's IMSI in the CdPA field of the UpdateLocation message. An intermediate STP would then global-title-translate the UpdateLocation message and route the message to the correct HLR. If the global title translation data for mapping the IMSI to the correct HLR is not pre-provisioned in the STP, the subsequent InsertSubscriberData transaction cannot occur. As a result, the MSISDN-to-HLR address translation cannot be learned either.
Accordingly, in light of these difficulties associated with conventional provisioning systems, there exists a long-felt need for improved methods and systems for provisioning translation information in a mobile services node address translation database.